id,summary,reporter,owner,description,type,status,priority,milestone,component,version,resolution,keywords,cc,os,architecture,failure,testcase,blockedby,blocking,related,differential
5424,Validate error under 7.2.1 caused by incomplete pattern warnings in new code gen (GADTs),dterei,simonpj,"the files compiler/cmm/Cmm.hs, compiler/cmm/CmmNode.hs and compiler/cmm/CmmStackLayout.hs all contain the following lines at the top:
{{{
{-# OPTIONS_GHC -fno-warn-incomplete-patterns #-}
#if __GLASGOW_HASKELL__ >= 701
-- GHC 7.0.1 improved incomplete pattern warnings with GADTs
{-# OPTIONS_GHC -fwarn-incomplete-patterns #-}
#endif
}}}
This causes a validation error when building with 7.2.1 as this version of GHC still seems to incorrectly warn about incorrect patterns despite the above comment. (The above comment is wrong anyway as the cpp if statement only triggers with GHC 7.2.1 and greater, not with GHC 7.0.1).
For now I've dealt with this simply by changing the cpp if statement to be:
{{{
#if __GLASGOW_HASKELL__ >= 703
...
}}}
Someone more familiar with the code and the state of '-fwarn-incomplete-patterns' should actually fix this up though.",bug,closed,normal,,Compiler,7.2.1,fixed,,,Unknown/Multiple,Unknown/Multiple,Building GHC failed,gadt/T5424,,,,